Grading machine



3 Sheets-Sheet l J. W. JOHNSTON GRADING MACHINE Filed Feb. l0, 1933 May 29, 1934.

J. W. JOHNSTON GRADING MACHINE May 29, 1934.

Filed Feb. l0, 1933 3 Sheets-Sheet 2 ma, y

= came May 29, 1934.

J. w. JOHNSTON GRADING MACHINE 3 Sheets-Sheet 3 Filed Feb. l0, 1953 M s 1 x 11.111 .Eril ...IIL i E i K r. f ...1f i r.

MW @WWE Patented May 29, 1934 UNTED TATES PATNT OFFICE GRADING MACHINE Application February 10, 1933, Serial No. 656,110

12 Claims.

This invention relates to grading machines of the kind which grade died-out pieces f leather such as cut soies, taps, counters or other blanks, in accordance with the thickness of the thinnest spot as determined by the detector.

The term grading is herein used in its generic sense, as established in this art, to include stamping or marking each blank with its grade number, evening or skiving the blank to the grade thicklo ness of its thinnest spot, indicating the grades on a visual indlcator, and sorting or distributing the blanks according to their grades. Two or more species of grading devices may be and frequently are contained in one machine.

Since the present invention has to do particularly with the transmission and setting mechanism, by which the adjusting of the grading device is `controlled in accordance with the measurements determined by the detecting device, rather '2c than with the particular form of grading device nsed, it will be sumcient for an understanding of the invention to describe it in connection with one grading device; and by way of illustration a stamping or marking device has been selected, but it Will be understood that the invention is applicable also to machines employing other vspecies ci grading devices.

The general construction and operation of grading machines, of which the present invention is an improvement, is commercially Well-[known in the art and is set forth in numerous patents granted to Elmer P. Nichols and Leander A. Cogs- Well. By Way lof example, the Nichols Patent No. '1,130,321 dated March 42, 1915, maybe referred to f' as illustrating the general type of grading and evening machine to which the present invention :is applicable, yand the 'Cogswell Patent No. 1,366,- -389,dated January 25, 1921, may `be referred to as illustrating the kind of gate-controlling and stamp-operating :mechanism recommended.

It is a common characteristic of .such grading machines that each blank passing through -the machine `is measured by detecting rolls, which determine the thickness of the thinnest spot-of the rblank orof ya selected area vof the blank, and that the measuring vmovements imparted to the 4detecting or measuring rolls bythe blank are trans- L'nrtdtted .through 4a train ofv transmitting and setting 'mechanism ito ,adjust the grading 'device :or 'devices (formarking, evening, etc.) Ainacccrdance 'with the ,grade :measurement as determined by the #detecting rolls. Heretofore, `the ,measuring movements ,of the spring-pressed-detecting ro11,as vthe :roll :moved inresnonse ,to variations in i-thick- 'ness .ofzthe 4passing blank,.has actuated or moved (C1. lill-d3) either the Whole of the transmission mechanism, and sometimes also the grading device, cr part ci the transmission mechanism. Due to the Weight, the inertia, the momentum, and/or the resistance ofthe parts so moved, the load or stress Gt on the spring-pressed detecting roll was varied,

so that instead .of exerting at all times `a constant and uniform pressure on the blank, as is desirable, the roll exerted a varying pressure, which interfered with its delicacy of voperation and tended to inaccuracy of measurements, especially when the machine was operating on soit stock.

A principal feature of the present invention is to obviate this objection and to provide a grading machine wherein the detecting and measuring 7,0k mechanism, While it is performing its measuring function, operates Wholly independently of any part outside itself, and is Wholly uniniluenced by any extraneous stress or `load tending to distort the measurements.

To this end I separate the transmitting and setting mechanism into two independent trains oi elements, one ci which trains only is adjusted by the detecting roll Without affecting the other train, or any part thereof, vor the grading device, `While the other train is `connected to Vand is movable with the grading device, the grading device and the Alatte-r train lbeing normally .urged by a spring, not connected in any Way lthe measuring mechanism, in the direction rof one `extreme grade position of the grading device, but locked in the opposite extreme position with the spring .undei` tension (or equivalently under compression) storing up energy during :the enti-re .measuring operation of the detecting rolls, ytor .later actuating the grading device and its trai-n, at the conclusion ci lwhich measuring opera-tion the grading device and its train are automatically unlocked :and shifted by the spring to ,the position of adjustment determined by the first train.` In this Away the detecting roll actuates -only the rst t-rain,v which may be `made Ofcomparatively light and -unresisting construction-and is never required 4to -actuate the second train or any part thereof or the grading device, which are .actuated whollyby the spring, While the first train, or an element thereof, A,serves merely as ,a ycontroller to stop .the second train .and grad.- ing device -in the position determined yby the adjustment 4of .the first train.

For the ,sake ci clearness ,and ,conciseness .o f 1explanation, certain vparts only of Aa known type ,of grading machine will be described, uWil-ich.are necessary for an runder-standing of Ythe invention;

lil() other parts may be supplied from the prior art above referred to.

In the accompanying drawings,

Fig. 1 is a vertical, longitudinal, sectional View of parts of a grading machine embodying the invention;

Fig. 2 is a horizontal section on line 2 2 of Fig. 1;

Fig. 3 is Fig. 2;

Fig. 4 is Fig. 2; and

Fig. 5 is Fig. 2.

The soles or other blanks are fed into the machine automatically one at a time from a magazine 9, by usual feeding mechanism; or they may be fed in by hand. As each blank is fed in it is slid forwardly on table to a pair of continuously driven detecting or measuring rolls 11 and 12. Upon being discharged from between the detecting rolls 11 and 12 the blank is carried forward by a continuously driven chain conveyor 13 into position under the type wheel or marking wheel 14, by which the blank is automatically stamped or marked with a character indicating the thickness grade of the blank as determined by the detecting rolls 11, 12.

The marking wheel 14 is carried by a Vertically movable slide or plunger l5, which is automatically reciprocated to force the marking wheel downwardly against the blank when the forward end of the blank engages and depresses the trip 16, the marking wheel having been prea partial section on line 3 3 of a partial section on line 4 4 of a partial section on line 5 5 of 1- viously automatically adjusted to accord with the thickness measurement of the thinnest part of the blank as determined by the detecting rolls 11, 12.

The effective measuring or detecting operation begins when the blank engages the trip 17 and lifts the trip arm 18. The measuring or detecting operation ends when the rear end of the blank passes out from under the gate 19 and permits the latter to drop to the table 10.

While being propelled through the machine the blank is held down against the conveyor 13 by a spring pressed shoe 20 provided with anti-friction rollers which ride on the top side of the blank.

When the blank clears the trip 17a the trip arm 18 is permitted to drop, whereupon the measuring and grading instrumentalities are all restored to their initial position ready to receive and act upon another blank, and, ir" an automatic feed is used, another blank is ted forward from magazine 9. The blank is discharged from the machine upon a shelf or table 22.

The marking wheel is provided upon its periphery as usual with a series of printing or stamping characters indicating thickness grades, usually in terms of irons. Said wheel is xed Ito a short shaft 23, journaled in a bearing in the lower end of the vertically movable slide which normally occupies its elevated position. A pinion 24, fixed to shaft 23, meshes with a gear segment on the end of an arm 25, which is pivotally mounted on slide at 26. The arm 25 is connected through the usual link 27 with the usual endwise adjustable bar 28, one side of which is formed with rack teeth meshing with pinion 29. The pinion 29 is xed, as usual, to the upper end of a Vertical shaft 30. Fixed to the lower end of the shaft 30 is another pinion 31, meshing with a rack of teeth on one side of a rack bar 32, which slides in ways 33 on the frame of the machine.

The upper detecting roll is mounted, as usual, in fixed journal boxes, one of which is shown at 34 (Fig. l), while the lower detecting roll 12 is mounted in journal boxes, one of which is shown at 35, movable vertically toward and from the upper roll in ways on the machine frame. A crossbar or yoke 36 is secured to the under side of the journal boxes and is yieldingly urged upwardly by a pair of spring-pressed bell-crank levers, one 0f which is shown at 3'?.

The parts thus far described may be of usual and well-known construction.

The up and down motion of the movable detecting roll l2 in response to variations in thickness of a blank passing between the rolls 11 and 12, is transmitted to a controller arm 38, through a pair of links or rods 39 depending from yoke 36. One of the links 39 extends loosely through a hole in controller arm 38 and is provided on its end underneath arm 38 with a nut or head which positively lifts arm 38 when roll 12 rises. The controller arm 38 is normally held down against the heads of links 39 by its own weight, by gravity, which might be supplemented if desired by a spring. The controller arm 38 is rigidly fixed to a rockshaft 41, journaled at its ends in bearings on the machine frame. A short arm 42 is also fixed to rockshaft 41, or it might be made in one piece with arm 38, and the other link 39 is connected to arm 42 in the same manner that the first link 39 is connected to arm 38.

Loosely mounted on rockshaft 41 between arms 38 and 42, is an arm 43, formed at its free end with a gear segment 44, which meshes with a gear segment 45 fixed to rockshaft 46. The controller arm 38 carries a laterally projecting lug 3S, normally engaging the underside of segment arm 43, so that the controller arm 38 is free to swing up and down independently of the segment arm 43 when the latter occupies its uppermost position, which is its position while the detecting roll 12 is moving up and down in response to variation in thickness of the blank during the measuring operation.

Fixed to rockshaft 46 is a second gear segment 4), which meshes with a rack of teeth on the bottom of the rack bar 32. An adjustable stop screw 48 on the machine frame limits-the movement of the rack bar 32 toward the left (Figs. 1 and 2) under the influence of the usual spring-pressed bell-crank levers 37 acting through yoke 36, links 39, arm 38, lug 38a, arm 43, gear segment 45, shaft 46 and gear segment 40.

Normally and during the measuring operation, the rack bar 32 is locked in position against stop screw 48 by a gravity latch or detent 49, pivotally mounted at 50 on the machine frame and provided with a shoulder 52 which engages a shoulder 53 at the right-hand end of rack bar 32. In this position the latch 49 locks the rack bar 32 in its extreme retracted position, and consequently also locks lthe adjusting bar 28 in its extreme retracted position with the type wheel 14 in one of its extreme grade positions and the spring 51 under tension. The spring 5l has one end attached to the adjusting bar 28 and the other end attached to the frame of the machine, and normally tends to urge the adjusting bar 28, and consequently finish of the measuring operation, and at the cornpletion of the measuring operation the latch is automatically released to free the rack bar 32 and its connected parts, as will presently be described.

The free end of latch 49 extends immediately above a cam arm 54 fixed to a rockshaft 55, which is journaled on the machine frame. Fixed to the rockshaft 55 is another arm 56 carrying a stud 57 (Figs. 1 and 3), which engages a slot 58 in the free end of a lever 59, fulcrumed at 69 on the machine frame. The other end of lever 59 is connected by a link 6l with the usual gate 19.

Also fixed to rockshaft 55 is a pawl 62, which cooperates with a rack of ratchet teeth 63 formed on the outer face of a sector 64 constituting a part of the controller arm 38. When the gate 19 is held up the pawl 62 is disengaged from its ratchet; but when gate 19 drops off from the rear end of a blank at the completion of the measuring operation, the gate 19, acting through link 61, lever 59, pin and slot 57, 58, arm 56 and rockshaft 55, causes the pawl 62 to swing into engagement with rack 63, thus locking the controller arm 38 in the grade detecting position which it occupies at the moment.

The trip arm 18 (Fig. l), which is swung upwardly by the blank acting through trip 17 to start the measuring operation, is iixed to a rockshaft 65. At one end of rockshaft 65 is xed an arm 66 (Fig. 3), to the free end of which is pivotally connected a weighted, depending push rod 67, whose lower end abuts against the top side of a lever 68, fulcrumed at 69 on the machine i frame. The free end of lever 68 engages one arm of a bell-crank pawl member 70 (Figs. 3 and 5), whose other arm constitutes a pawl cooperating with a rack of ratchet teeth 71 on the side of sector 64. Pawl 70 is pivoted on the frame of the machine at 72 and is urged toward ratchet 71 by a spring 73.

The ratchets 63 and 71, and their respective pawls 62 and 70, are opposed so that when pawl 70 is in engagement with its ratchet 71 and pawl 62 is disengaged from its ratchet 63 (which is the condition during the measuring operation), the controller arm 38 is held against downward moven ment when thicker areas of the blank are encountered by the detecting rolls, but is free to move upwardly in response to successive thinner spots encountered by the detecting rolls, thus preserving the measurement of the thinnest spot of the blank as determined by the detecting rolls; and when both pawls are engaged with their ratchets the controller arm 38 is locked against movement in either direction. The measuring operation is started when pawl 70 engages its ratchet 71 and ends when pawl 62 engages its ratchet 63.

The rockshaf t 65 has fixed to it a third short arm 74 (Fig. 3) cooperating with a roller 75 at the free end of a lever 76 fulcrumed on the machine frame at 77. The opposite end of lever 76 is connected by a link 78 with the gate 19.

When the rear end of a blank passes out from under trip 17a, which is mounted on the same arm 18 as trip 17, the arm 18 is permitted to fall and acts through rockshaft 65, arm 66, rod 67 and lever 68 to disengage pawl 70 from its ratchet 71; at the same time the fall of arm 18 acts through arm- 74, lever 76 and link 78 to raise the gate 19, and also through link 61, lever 59, arm 56 and rockshaft 55 to disengage pawl 62 from its ratchet 63, thereby unlocking both pawls from controller arm 38.

The operation of the machine is as follows: The initial position of the parts is as shown in the drawings, with the gate 19 elevated or open, ihe trips 17 and 17a lowered and resting on the machine bed, both pawls 76 and 62 disengaged, the detecting rolls 11 and l2 closed toward each other in their extreme minimum grade position by the spring-pressed levers 37, the controller arm 38 and segment arm 43 in their uppermost position, the rack bar 32 locked by the detent 39 in its extreme retracted position, and the adjusting bar 28 and the grading devices governed thereby in their extreme minimum grade position with the actuating spring 51 under tension.

When a blank is fed forward on table 10 underneath gate 19, its advance end enters between the detecting rolls 11 and 12. Roll 12 is pressed downwardly by the blank, and the controller arm 38 moves down with it but independently of and without affecting segment arm 43 or the grading device or the actuating spring 51 or any part of the train of mechanism connecting the segment arm with the grading device, since those parts remain locked by latch 49 and the lug 38'(l is free to move downward away from arm 43. When the advance end of the blank engages and lifts trip 17, the trip arm 18 is swung upwardly, which both lowers the gate 19 on to the top of the passing blank and permits the pawl 70 to engage its ratchet 71. This begins the elective measuring operation on the blank, and as successive thinner spots of the blank are encountered by the detecting rolls, such increments of thinness are transmitted to and preserved by the controller arm 38; but thicker measurements will not be transmitted to arm 38, which is locked against downward movement by pawl 70. Any downward movement of roll 12 will be permitted by the loose connection between roll 12 and arm 38. The trip 17 is adjusable on arm 18, as usual, so as to vary the length of that part of the blank which it is not desired to measure, such as the heel part of a sole. When the rear or trailing end of the blank, on which the gate 19 is resting, passes out from under the gate, the gate drops to the table (such movement of the gate independently of the lever 76 being permitted by the pin and slot connection 87 between the lever 76 and the link 78), and the fall of the gate acts through link 61 and lever 59 to engage the pawl 62 with its ratchet 63. This ends the measuring operation and leaves the controller arm 38 locked against movement in either direction.

At the same time when pawl 62 is set into its ratchet, cam arm 54 lifts the latch or detent 49 and releases the rack bar 32 and allows spring 51 to shift the adjusting bar 28 endwise toward its opposite position, and correspondingly to adjust the grading device (marking wheel or the like). Said movement of the adjusting bar 28 under the influence `of spring 5l acts through gear 29, shaft 30, gear 31, rack bar 32, gear segment 40, shaft L16 and gear segment 45, to swing the segment arm 43, which constitutes a stop arm, until it is arrested against the stop lug 38a on the controller arm 38, in which position the grading device will be adjusted in accordance with the grade measurement of the blank as determined by and transmitted to the controller arm 38. When the blank reaches and depresses the trip 16 a single vertical reciprocation of the slide 15 is eected by usual mechanism to cause the marking Awheel to mark the blank. It will also be understood that when a skiving or evening device is used in the maL chine, the adjusting bar 28 will carry the usual GLS wedge-shaped blocks or incline's on its under side, which determine the adjustment of the skiving device, as commonly known in this art and mentioned in said Nichols Patent No. 1,130,321.

When the rear end of the blank passes out from under trip 17'@L (which is adjustable on arm 18 to vary the timing of its action) the arm 18 falls and acts through the connections already described to lift the gate 19 and simultaneously to disengage both pawls and 62. Thereupon the spring-pressed levers 37 will raise the lower detecting roll 12 and the controller arm 38 to their initial, elevated position. The upward movement of controller arm 38 acts through lug 38a, stop arm 43, and gear segments 45 and 40 to restore rack bar 32 to its initial position against stop 48, where it is automatically locked by the gravity latch 49; and the rack bar 32 in turn restores the adjusting bar 23 and the grading device adjusted thereby to their initial eXtreme positions, with the spring 51 under tension. The machine is now ready to grade another blank and the cycle of operations is repeated.

As already stated, the machine may be fed by hand or by an automatic feeding mechanism. When a feeding mechanism is used the blanks are stacked in a magazine 9 and are fed forward into the machine one at a time from the bottom of the stack by a feed slide of known construction (not shown) movable back and forth on the falls it acts through rockshaft 65, arm 81 and clutch-actuating bar 82 to couple a single-revolution-and-stop clutch of known construction, by which the crank arm is connected to a continuously rotating member, thereby imparting a single revolution to crank arm 79 and a single reciprocation to feed slide. Thus the departure of one blank from the machine automatically causes the feeding in of another blank from the magazine 9.

In order to cushion or yieldingly check the movements of the parts under the influence of spring 51, and also under the influence of the spring-pressed levers 37, a double acting dash pot 83 (Fig. 4) is provided, whose piston rod 84 is pivotally connected to an arm 85 fixed to rockshaft 46. The lower end of the dash pot 83 is pivotally connected at 86 to the frame of the machine. Thus, when the latch 49 is disengaged from rack bar 32, the dash pot cushions the shock of the movement of the parts which are actuated by spring 51; also the dash pot cushionsY the shock of the movement of the parts moved by the spring-pressed levers 37 when the machine is restored to its initial, normal position.

It will thus be seen that the setting mechanism, which controls the final adjustment of the grading device in accordance with the measurements determined by the detecting rolls, comprises two independent trains of elements. The rst of said trains includes the controller arm 38 and the parts connecting the controller arm with the movable detecting roll 12, and this train only is adjusted directly by and in response to the measuring movements of the detecting roll 12, without affecting the other train or any part thereof.

The detecting roll is therefore required to move only a few and relatively light and easily operated parts during the measuring operation, and is relieved of the load, the inertia and the resistance of operating the Whole or any part of the second train (including the actuating spring 51) or the grading device, or the dash pot 83. This greatly improves the accuracy and delicacy of the detecting and measuring operation, as well as saving undue wear and tear 'of the parts. The second of said independent trains includes the stop arm 43 and the parts connecting the stop arm 43 with grading device. The second train and the grading device are held locked by the latch or detent 49 at one extreme grade position of the grading device with the spring 51 under tension during the entire measuring operation of the detecting rolls and controller arm 38, whose lug 38a is free to move downwardly away from the stop arm 43, while the stop arm 43 and parts connected to it are locked immovable. When the measuring is completed and the final locking of the controller arm 38 is effected by pawl 62, the same nal locking action simultaneously releases latch 49 and unlocks the second train, whereupon the spring 51, acting upon adjusting bar 28, shifts the parts toward their opposite extreme position until the stop arm 43 is arrested against lug- 382L of the controller arm, thus bringing the second train and the grading device to the position of adjustment corresponding to that of the first train. And iinally when the blank clears trip 17a, both locks' (62 and '70) of the first train are unlocked, and the springpressed levers 37 restore the detecting roll 12 and controller arm 38 to their elevated position, and at the same time restore the second train and the grading device to their initial extreme positions with the spring 51 under tension, in which position the parts are automatically locked by the gravity latch 49. It will be understood that the power of the spring-pressed levers 37 exceeds that of the spring 5l.

Thus, during the measuring operation, the detecting and measuring mechanism (which may be considered to be composed of the detecting roll, the controller 38, the connections between the same, and the spring-pressed levers 37) operates wholly independently of anything else outside of itself, and is wholly uninfluenced by any stress or load which might tend to interfere with or distort the measurement,

I claim:

1. A grading machine comprising detecting and measuring mechanism for determining and preserving the thickness grades of successive blanks passing therethrough, an adjustable grading device and train of setting mechanism connected to and movable with the grading device, and means to shift the grading device and its setting mechanism to the position of adjustment in accord with the position of the detecting and measuring mechanism after the completion of the measuringl operation, the detecting and measuring mechanism operating in both directions wholly independently of and uninuenced by the load or stress of said grading device, or said setting mechanism, or said shifting means, during the measuring operation of the detecting and measuring mechanism, the grading device and its train of setting mechanism being held immovable during the measuring operation.

2. A grading machine comprising detecting and measuring mechanism for determining and preserving the thickness grades of successive blanks passing therethrough, an adjustable grading device and train ci setting mechanism connected to and movable with the grading device, and means to shift the grading device and its setting mechanism to the position of adjustment in accord with the position of the detecting and measuring mechanism after the completion of the measurincr operation, the detecting and measuring mechanism operating in both directions Wholly independently of and uniniluenced by the load or stress of said grading device, or said setting mechanism, or said shifting means, during the measuring operation of the detecting and measuring mechanism, the grading device and its train of setting mechanism being held immovable during the measuring operation, and means to restore the grading device and its setting mechanism and shifting means to initial position by the return of the detecting and measuring mechanism to its initial position.

3. A grading machine comprising detecting and measuring mechanism for determining and preserving the thickness grades of successive blanks passing therethrough, an adjustable grading device and train of setting mechanism connected to and movable with the grading device, the detecting and measuring mechanism operating in both directions wholly independently of and uninfluenced by the load or stress oi any part other than itself during the measuring operation of the detecting and measuring mechanism, the grading device and its train of setting mechanism being held immovable during said measuring operation, and means to cause the grading device and its setting mechanism to shift to the position of adjustment in accord with the position of the detecting and measuring mechanism after the completion of the measuring operation.

4. A grading machine comprising detecting and measuring mechanism for determining and preserving the thickness grades of successive blanks passing therethrough, an adjustable grading device and train of setting mechanism connected to and movable with the grading device, the detecting and measuring mechanism operating in both directions wholly independently of and uninuenced by the load or stress of any part other than itself during the measuring operation of the detecting and measuring mechanism, the grading device and its train of setting mechanism being held immovable during said measuring operation, and means to cause the grading device and its setting mechanism to shift to the position of adjustment in accord with the position of the detecting and measuring mechanism after the completion of the measuring operation and means to restore the grading device and its setting mechanism to initial position by the return of the detecting and measuring mechanism to its initial position.

5. A grading machine comprising detecting rolls for measuring successive blanks according to thickness, an adjustable grading device, setting mechanism for controlling the grading device in accordance with the measurement determined by the detecting rolls, said setting mechanism comprising two independent trains of elements, one of which trains only is adjusted by the detecting rolls without affecting the other train, while the other train is connected to and movable with the grading device, a spring normally urging the grading device and its train toward one extreme grade position of the grading device, means to lock the grading device and its train in the opposite extreme grade position of the grading device during the measuring operation of the detecting rolls, means automatically to unlock the grading device and its train after completion of the measuring operation to permit the grading device and its train to move under the influence of said spring,

and means to stop the grading device and its train at the position of adjustment of the rst train.

6. A grading machine comprising detecting rolls for measuring successive blanks according to thickness, an adjustable grading device, setting mechanism for controlling the grading device in accordance with the measurement determined by the detecting rolls, said setting mechanism comprising two independent trains of elements, one of which trains only is adjusted by the detecting rolls Without affecting the other train, while the other train is connected to and movable with the grading device, a spring normally urging the grading device and its train toward one extreme grade position of the grading device, means to lock the grading device and its train in the opposite extreme grade position of the grading device dur-l ing the measuring operation of the detecting rolls, means automatically to unlock the grading device and its train after completion of the measuring operation to permit the grading device and its train to move under the iniluence of said spring, means to stop the grading device and its train at the position of adjustment of the first train and means whereby the grading device and its train are restored to their initial extreme grade position and there locked by the return of the den tecting rolls and the rst train to normal position.

'1. A grading machine comprising detecting rolls for measuring successive blanks according to thickness, an adjustable grading device, setting mechanism for controlling the grading device in accordance with the measurement determined by the detecting rolls, said setting mechanism comprising two independent trains of elements, one of which trains only is adjusted by the detecting rolls Without affecting the other train, While the other train is connected to and movable with the grading device, means controlled by the blank for automatically locking the rst train at the end of the measuring operation, a spring normally urging the grading device and its train toward one eXtreme grade position of the grading device, means to lock the grading device and its train in the opposite extreme grade position of the grading device during the measuring operation of the detecting rolls, means automatically to unlock the grading device and its train when the rst train is locked after completion of the measuring operation to permit the grading device and its train to move under the influence of said spring, and means to stop the grading device and its train at the position of adjustment of the first train.

8. A grading machine comprising detecting rolls for measuring successive blanks according to thickness, an adjustable grading device, setting mechanism for controlling the grading device in accordance with the measurement determined by the detecting rolls, said setting mechanism comprising two independent trains of elements, one ci which trains only is adjusted by the detecting rolls Without affecting the other train, while the other train is connected to and movable with the grading device, one of said trains including a stop member cooperating with the other train, a spring normally urging the grading device and its train toward one extreme grade position of the grading device, means to lock the grading device and its train in the opposite eXtreme grade position of the grading device during the measuring operation of the detecting rolls, and means automatically to unlock the grading device and its train after completion of themeasuring operation to permit the grading device and its train to move under the inuence of said spring until said stop member arrests the grading device and its train in the position of adjustment of the first train.

9. A grading machine comprising a pair of detecting rolls for measuring successive blanks according to thickness, one of which is yieldingly urged toward the other, an adjustable grading device, setting mechanism for controlling the grading device in accordance with the measurement determined by the detecting rolls, said setting mechanism comprising two independent trains of elements, one of which trains only is adjusted by the movable detecting roll without ar"- fecting the other train, while the other train is connected to and movable with the grading device, the rst train including a pivotally supported controller arm adjusted by the measuring movements of the movable detecting roll and having two racks of teeth, two automatically controlled pawls cooperating respectively with said racks of teeth, one of which is engaged with its rack to start the measuring operation and the other of which is engaged'with its rack to end the measuring operation, the other train including a pivotally supported stop arm cooperatively associated with the controller arm, a spring by which the stop arm is yieldingly urged toward the controller arm, a latch by which the stop arm is locked against adjustment with the controller arm, and means for automatically releasing the latch to permit the stop arm to shift under the influence of said spring into position corresponding to the adjustment of the controller arm after the completion of the measuring operation.

10. A grading machine comprising a pair of detecting rolls for measuring successive blanks according to thickness, one of which is yieldingly urged toward the other, an adjustable grading device, setting mechanism for controlling the grading device in accordance with the measurement determined by the detecting rolls, said setting mechanism comprising two independent trains of elements, one of which trains only is adjusted by the movable detecting roll without affecting the other train, while the other train is connected to and movable with the grading device, the rst train including a pivotally supported controller arm adjusted by the measuring movements o the movable detecting roll and having two racks of teeth, two automatically controlled pawls cooperating respectively with said racks of teeth, one of which is engaged with its rack to start the measuring operation and the other of which is engaged with its rack to end the measuring operation, the other train including a pivotally supported stop arm cooperatively associated with the controller arm, a spring by which the stop arm is yieldingly urged toward the controller arm, a latch by which the stop arm is locked against adjustment with the controller arm, means for automatically releasing the latch to permit the stop arm to shift under the iniluence of said spring into position corresponding to the adjustment of the controller arm after the completion of the measuring operation and means to restore the stop arm to its initial locked position when the controller arm is returned to normal position.

11. A grading machine comprising a grading device, an adjusting bar for adjusting the grading device, a spring normally urging the adjusting bar and grading device toward one extreme grade position, a detent to hold the adjusting bar in the opposite eXtreme grade position, a pair of detecting rolls one of which is movable toward and from the other and is yieldingly pressed toward the other, a controller adjustable in accordance with measuring movements of the movable detecting roll without affecting the adjusting bar, a trip in the path of the blank for releasing the detent after the completion of the adjustment of the controller and permitting the adjusting bar to move under the iniluence of its spring, and connections between the adjusting bar and controller to stop the adjusting bar in accordance with the setting of the controller.

12. A grading machine comprising a grading device, an adjusting bar for adjusting the grading device, a spring normally urging the adjusting bar and grading device toward one extreme grade position, a detent to hold the adjusting bar in the opposite extreme grade position, a pair of detecting rolls one of which is movable toward and from the other and is yieldingly pressed toward the other, a controller adjustable in accordance with measuring movements of the movable detecting roll without ailecting the adjust- 1 ing bar, a trip in the path of the blank for releasing the detent after the completion of the adjustment of the controller and permitting the adjusting bar to move under the influence of its spring,

and connections between the adjusting bar and controller to stop the adjusting bar in accordance with the setting of the controller and to return the adjusting bar to its initial extreme position when the detecting roll and controller are returned to normal position.

JAMES W. JOHNSTON. 

